1. Field of the Invention
This invention pertains to missile launching apparatus. In particular, it pertains to self powered missile launching apparatus which accelerates the missile to launch speed during initiation of a rocket motor. In even greater particularity, the present invention pertains to boost assisted missile launchings which do not require external fasteners on missiles which interfere with aerodynamic performance.
2. Description of the Prior Art
Launching apparatus for missiles, rockets etc. are well known in the art and comprise many methods and techniques. Most of these methods however can be lumped together under the general heading of pneumatic techniques. These techniques require a high cost for maintenance, these launching systems have to be cleaned after a small number of firings. This cleaning requirement limits the number of missions aircraft can fly before maintenance must be performed.
Prior art patents include U.S. Pat. Nos. 3,605,549 to Moskowitz et al., 3,968,947 to Schlegel et al., and 4,040,334 to Smethers Jr. These prior art patents along with numerous other prior art patents rely on a compressed fluid, such as air, to propel the missile or other desired object into flight. Moskowitz et al. provides a retaining area where the exhaust gases of the rocket motor build up to a predetermined pressure such that they can overcome the effects of a restraining system and the accompanying friction and inertia of such a system. The Moskowitz et al. device results in an excessively hot launch tube along with consumption of rocket fuel prior to the rocket actually entering flight.
Schlegel et al. provides for a pneumatic launching apparatus using a propelling tube which is driven forward under pressure from a supporting system. This invention conserves the onboard fuel supply of the launched aircraft until it is inflight. For any heavy object, the length of the launching tube becomes prohibitively long resulting in loss of pressure as the launching tube extends.
The Smethers patent provides the means for launching missiles from an aircraft through a tube. The missiles are propelled out of the tube by compressed air which permits a higher initial velocity on the missile being launched. The greater velocity and conserved fuel permits a greater range for the missile.
These and numerous other prior art devices all seek to overcome the basic problems of missile launch from aircraft. These problems include avoiding physical bumping of the missile and aircraft, fuel consumption by the missile to obtain free flight, guidance control of the missile to offset uneven flight dynamics caused by external fasteners and scorching of the aircraft by missile exhaust.
The most common technique for launching missiles requires some sort of rail launcher or bomb rack attachment carried underneath the wings of the aircraft which is uniquely designed to the particular type of missile to be launched. The missile is aimed or locked on target and then fired through connecting electronics which ignite the rocket motor of the missile in question. The thrust provided by the missile is required to overcome the moment of inertia aerodynamic drag and static friction inherent in breaking free of any launch track as well as overcoming the restraining force of any safety devices used to lock the missile in place prior to launch. These launch requirements result in the missile consuming a significant percentage of its initial fuel supply to become airborne. This results in reduction of the possible range the missile could otherwise attain. Furthermore, the missile requires some sort of fastening or coupling to attach it to the aircraft prior to launch. These couplings, which have always been external, are further constrained by the need to hold the ordnance at a reasonable distance from the airfoil of the aircraft such that air turbulence during the initial moments of launch does not cause the missile to be bounced against the aircraft. Such contact causes damage to both the missile and the aircraft. Fasteners on the external surfaces of the missile further increase aerodynamic drag on the missile resulting in decreased range capability. Furthermore, the external fasteners result in unbalanced air flow around the missile which require compensation through guidance mechanisms within the missile.